1. Field of the Invention
The present invention relates to a portable medical liquid infusion device which is capable of quantitatively measuring medical liquid infusion rate, and of informing a drip interval by a recognizable signal when the medical liquid infusion rate is adjusted. More particularly, the present invention relates to a portable medical liquid infusion device which receives an input of a medical liquid infusion rate (cc/hour), the quantity of medical liquid to be infused, or the length of time for infusion, and outputs a recognition signal corresponding to the input, thereby allowing a drip interval to be easily adjusted, and which quantitatively calculates and outputs a medical liquid infusion rate on the basis of a count input which is received in accordance with a drip interval when measuring the medical liquid infusion rate, wherein the medical liquid infusion device judges a count input having an irregular interval as an erroneous input, and renders another count input to be made again through automatic resetting, whereby the medical liquid infusion device can output a correct measurement result only, and also can output the length of time for infusing the remaining medical liquid when measuring the medical liquid infusion rate.
2. Description of the Prior Art
Referring to FIG. 1, a conventional intravenous (IV) injection system for directly administrating medical liquid to a vein includes: a medical liquid bottle 10 in which medical liquid 11 is contained; a dripper 20 consisting of an insertion needle 21 inserted through a sealing plug of the medical liquid bottle 10, so that the medical liquid 11 flows through the insertion needle 21, and a drip chamber 22 within which the medical liquid 11 drops in the form of droplets 23; an injection needle 50 inserted into a vein; an infusion tube 40 interconnecting the dripper 20 and the injection needle 50 so that the medical liquid flows through the infusion tube 40; and a medical liquid regulator 30 fitted on a middle part of the infusion tube so as to regulate the flow rate of the medical liquid.
Intravenous infusion using the above-mentioned IV system is conducted by fixedly positioning the medical liquid bottle 10 above the injection needle 50, so that the medical liquid 11 can be naturally infused by its weight. In addition, the infusion rate of the medical liquid is controlled in such a manner that a user adjusts the medical liquid regulator so that the drop period of the droplets 23 can be changed, and the user checks the drop period by counting the number of droplets while seeing the droplets by the naked eye and measuring the length of consumed time with an ordinary watch. In general, a doctor writes the number of droplets dropping per minute on a chart, or writes the quantity of medical liquid to be infused per hour or per day on the chart in CC unit, so that a nurse regulates the drop rate of the droplets in accordance with the above-mentioned method.
However, since the above-mentioned medical liquid infusion rate regulating method is conducted on the basis of the user's eyes and experience, it is impossible to correctly regulate the medical liquid infusion rate. In general, although the medical liquid should be infused in a precisely regulated rate depending on the age and condition of a patient, the type of medical liquid, and the medicaments contained in the medical liquid, the above-mentioned medical liquid infusion method may incorrectly regulate the medical liquid infusion rate, which may cause a medical malpractice.
Accordingly, it is necessary to quantitatively measure the medical liquid infusion rate so as to adjust the medical liquid regulator 30. For this purpose, the prior art has proposed in Korean Un-examined Patent Publication No. 10-2004-0048889, entitled “Volumetric Flow Measuring Apparatus for intravenous Injection Set,” and Korean Un-examined Patent Publication No. 10-2005-0039780, entitled “System for Measuring Flow Rate of Ringer's solution Using Image Signal Processing.” However, since the apparatus and system measure the number of dropping droplets 23 and the quantity of medical liquid by sensing the droplets 23 dropping in the drip chamber with infrared (IR) rays, they not only lack accuracy due to the influence of external light, but also cause inconvenience and costs in connection with installing the measuring apparatus or system, by which the apparatus or system have not been actually produced on a market scale.
In addition, Korean Registered Utility Model Publication 20-0336940, entitled “Automatic Detection and Prevention System of Drug Dripper,” proposed an apparatus provided with a drop carrier which is moved each time when a droplet drops in a drip chamber, so that the dropping of droplets can be sensed from the outside. However, the apparatus has not been practically used since it is necessary to change the typically used drip chamber 22 in terms of construction, and its drip chamber and measuring device are very complicated.
In addition, since the above-mentioned conventional technologies basically use a volume measuring method by means of a sensor, the infusion rate of medical liquid cannot help being regulated, only depending on the measuring device. Therefore, since it is difficult to cope with the malfunction of such a measuring device, what is needed is a simple and convenient measuring device which does not suffer from minor troubles when it is used by a doctor in charge or a nursing staff.
As the above-mentioned prior art systems, apparatuses and devices have not been practically used due to their own problems, a nursing staff in a clinic or hospital calculates medical liquid infusion rate by measuring the length of drop time of droplets with a stopwatch by a predetermined number of times. In such a method, since it is necessary to check the stopwatch and the drip chamber 22 while alternately watching them, a large error may occur in terms of calculated infusion rate. Therefore, what is needed is a medical liquid infusion rate measuring device which can be easily used by a non-skilled nursing staff.
For this purpose, in Korean Patent No. 10-0706945, entitled “medical liquid Infusion Rate Measuring Device,” the present applicant proposed an apparatus capable of measuring medical liquid infusion rate by receiving inputs of droplet drop period by a set number of times.
In addition, in Korean Patent No. 10-0872089, entitled “medical liquid Infusion Supporting Device,” the present applicant proposed a medical liquid infusion supporting device which calculates the quantity of medical liquid infused per unit time on the basis of the preset volume of a droplet, thereby determining the drop period of droplets, and outputting acoustic waves in accordance with the determined drop period, so that the drip interval can be regulated.
However, prescriptions for medical liquid infusion are frequently rendered in relation to the quantity of medical liquid to be infused and the length of time for infusion, although such prescriptions are occasionally rendered in relation to the quantity of medical liquid to be infused per unit time (cc/hr or gtt/min). Therefore, the above-mentioned systems, apparatuses and devices have problems in that there are difficulties in that a nursing staff should calculate the quantity of medical liquid to be infused and the length of time for infusion through mental arithmetic or the like, convert them into information for the quantity of medical liquid to be infused per unit time, and then input the information, and further more, if there is an error in calculation, a medical malpractice may be caused. Therefore, what is needed is a device which can output a drip period, even if the information for the quantity of medical liquid and the length of time for infusion, rather than the information for the infusion quantity of medical liquid per unit time, is input.
Meanwhile, the above-mentioned systems, apparatuses and devices have employed a method of measuring medical liquid infusion rate, which is executed in such a manner that if a user pushes a count input key to be inconsistent with a drip period by mistake, the user recognizes the error, re-pushes the count input key by a preset number of times, and then measures the medical liquid infusion rate. However, since the method relies only on the user's judgment in checking the drip interval, there is a problem in that if the user completes the measurement of medical liquid infusion rate without recognizing an error caused at the time of determining the count input time interval, the error cannot help increasing the error range, even if the error is trivial, due to the characteristic of the systems, apparatuses and devices that determine the number of droplets, which is proportional to the length of consumed time as the length of time consumed for conducting count inputs in relation to the number of count input times.